I may have found it, or at the very least, a workaround.
Settings->general->restrictions.

It was completely off. Once in there and turned on, I set "require password" to "immediately". There is also a "15 minutes" setting instead of immediately, but I'm not rich enough to try that setting and keep buying things to see if it worked

Password not required for ANY purchase (not just free)

Originally Posted by dimp51

My son checked his iTunes account & found out that that his 4 yr old daughter had $158.82 in app purchases.

Whoa! He really needs to enable restrictions on his device especially for in-app purchases. Because my youngest son play a lot of games and watch cartoons via Netflix on my iPad, I have restrictions enabled before instance, he cannot make any in-app purchases, he cannot delete any apps & he cannot purchase any apps.